Cleptelmis addenda

Riffle beetles in the family Elmidae are associated with flowing water habitats, particularly riffles—shallow, turbulent sections of streams and rivers with rocky substrates. Cleptelmis addenda likely inhabits similar lotic environments with well-oxygenated water.

North America. Specific regional records are limited; distribution records from GBIF indicate presence in North America without finer-scale detail.

Elmidae larvae are aquatic and typically require 1–3 years to develop, depending on species and environmental conditions. Adults are generally short-lived and primarily reproductive. Specific life cycle details for C. addenda have not been documented.

Adult riffle beetles are known to crawl on submerged substrates rather than swim. They are strongly associated with the benthic zone of streams. Whether C. addenda exhibits specific behavioral traits distinct from congeners has not been reported.

Riffle beetles contribute to nutrient cycling in stream ecosystems through grazing on periphyton and detritus. As members of the benthic community, they serve as food for fish and other aquatic predators. The specific ecological role of C. addenda has not been studied.

No direct human relevance has been documented for this species. Riffle beetles are occasionally used as bioindicators of water quality in stream monitoring programs due to their sensitivity to pollution and habitat degradation.

• Cleptelmis ornataCongener in the same genus, distinguished by differences in elytral sculpture and coloration; C. addenda was described from specimens originally misidentified as C. ornata.

• aquatic
• riffle beetle
• stream insect
• Elmidae

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• Catalogue of Life